PHP: How to create unique short string IDs with PHP & MySQL

IDs are often numbers. Unfortunately there are only 10 digits to work with, so if you have a lot of records, IDs tend to get very lengthy. For computers that’s OK. But human beings like their IDs as short as possible. So how can we make IDs shorter? Well, we could borrow characters from the alphabet as have them pose as additional numbers…. Alphabet to the rescue!

I created this function a long time ago. Time to be nice and share.

More is Less – the ‘math’

The alphabet has 26 characters. That’s a lot more than 10 digits. If we also distinguish upper- and lowercase, and add digits to the bunch or the heck of it, we already have (26 x 2 + 10) 62 options we can use per position in the ID.

Now of course we can also add additional funny characters to ‘the bunch’ like – / * & # but those may cause problems in URLs and that’s our target audience for now.

OK so because there are roughly 6x more characters we will use per position, IDs will get muchshorter. We can just fit a lot more data in each position.

Convert your IDs

Now unlike Database servers: webservers are easy to scale so you can let them do a bit of converting to ease the life of your users, while keeping your database fast with numbers (MySQL really likes them plain numbers ; ).

To do the conversion I’ve written a PHP function that can translate big numbers to short strings and vice versa. I call it: alphaID.

The resulting string is not hard to decipher, but it can be a very nice feature to make URLs or directorie structures more compact and significant.